Magnifying narrow-band imaging versus magnifying white-light imaging for the differential diagnosis of gastric small depressive lesions: a prospective study

Abstract

Background: The accurate diagnosis of gastric small depressive lesions (SDLs), including gastritis and cancerous lesions, is difficult with conventional endoscopy when using white-light imaging (WLI). Narrow-band imaging (NBI) is expected to make a more accurate diagnosis of gastric SDLs than WLI because it provides better visualization of the mucosal surface and microvascular architecture when combined with magnifying endoscopy.

Objective: To compare the real-time diagnostic accuracy of magnifying WLI and magnifying NBI for gastric SDLs.

Design: Prospective study.

Setting: National Cancer Center Hospital East, Kashiwa, Japan.

Patients: Fifty-seven lesions in 53 consecutive patients were analyzed: 30 cancers and 27 benign lesions.

Interventions: If previously undiagnosed gastric SDLs smaller than 10 mm were identified during an endoscopic examination, magnifying observation with both WLI and NBI was performed for each SDL. Endoscopic diagnosis of SDLs was made by each method on site.

Main outcome measurements: The diagnostic accuracy and the time required for diagnosis.

Results: The diagnostic accuracy was significantly higher for NBI than for WLI (79% vs 44%; P = .0001), as was its sensitivity (70% vs 33%; P = .0005). The diagnostic specificity of NBI (89%) was higher than that of WLI (67%), but the difference was not statistically significant. The time required for the diagnosis was equivalent with both methods.

Limitations: Single-center study, small sample size.

Conclusions: Adding NBI to the WLI examination is essential for making an accurate diagnosis of gastric SDLs compared with magnifying WLI alone. (UMIN Clinical Trials Registry identification number C000000421).